diff --git a/lib/sidekiq/processor.rb b/lib/sidekiq/processor.rb
index 754a4541..26edce3c 100644
--- a/lib/sidekiq/processor.rb
+++ b/lib/sidekiq/processor.rb
@@ -110,6 +110,7 @@ module Sidekiq
         end
       end
       sleep(1)
+      nil
     end
 
     def process(work)